


Hamster Girl

by suicunespurr



Category: Miraculous Ladybug, 干物妹!うまるちゃん | Himouto! Umaru-chan (Anime)
Genre: F/M, Fluff and Crack, Hoodies, Ultimate Mecha Strike 3, degenerate, hamster - Freeform, hamster hoodie
Language: English
Status: Completed
Published: 2018-06-19
Updated: 2018-06-19
Packaged: 2019-05-25 16:42:00
Rating: General Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,385
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/14981252
Author URL: https://archiveofourown.org/users/suicunespurr/pseuds/suicunespurr
Summary: Everyone has their secrets. Marinette has a few, namely a few secret identities. Warning: Reveals Ahead!





	Hamster Girl

**Author's Note:**

> Summarization for those who don't know about Himouto! Umaru-chan: Umaru is the pretty, straight A student at school, but when she comes home, she dons on her hamster hoodie and becomes a gaming degenerate.

With a bright flash of pink over the Dupain-Cheng Bakery, Marinette dropped down inside her room, her work as resident heroine Ladybug done for the night.

“Tikki, I’m so exhausted,” vented the teenage girl as she collapsed on her bed, her eyes trying to find her kwami.

Tikki floated into view with a cookie already in hand.

“I believe it, that akuma took over an hour for you and Chat Noir to beat.”

Marinette groaned at the recollection of the speedy akuma that had been near impossible to catch if not for the two lucky charms she used that night.

“I need a break,” she sighed as she sat up and began heading down from her loft.

“But Marinette, you still have homework you need to do.”

“Just a little break Tikki, just to clear my head,” offered Marinette as she sat at the computer, pushing her schoolwork to the side. Maybe looking at pictures of fashion would clear her head. But that might lead her on a moment of inspiration, then she would never do her work. Maybe staring at pictures of Adrien would help. But who knows if she would get anything done if she started on that train. Maybe an episode of some show would help. Or maybe looking up cute animals.

She opened her browser on her computer and typed in cute animals. Scrolling down a bit she saw a picture of some hamsters. Clicking on the image of the hamsters, she proceeded to look at more hamsters until something caught her eye. It was a chibi anime girl dressed in a hamster hoodie. Curious, she clicked on the image, revealing more images of the girl, including a poster for a show.

Himouto! Umaru-chan

* * *

_Some months later..._

Chat Noir sat on the rooftop of the school, contemplating his life choices, as he stared at one of them across the street.

It had been eight hours since he found out his Lady was Marinette Dupain-Cheng. A revelation that caused him to give his kwami a full lecture about the pros and cons about Marinette knowing his identity as well. True, Chat discovering Ladybug’s identity had been an accident, but if he knew, shouldn’t she know his?

Plagg had been useless as usual, munching on cheese and saying “follow your heart kid.”

Right now his heart was telling him Marinette should know her partner was also Adrien Agreste, her friend.

His heart was also telling him that this could lead to a potential romantic relationship with his lady.

His heart was also telling him Marinette may accuse him for liking her only because she was Ladybug.

So maybe he should make more of an effort to get to know her better. That seemed reasonable. But should he reveal now or after he got to know her?

Probably now, wouldn’t want to confuse her.

Chat stood from his perch, rolling his shoulders as he looked at the window across from him. The light was still on, but he hadn’t seen any sign of Marinette other than when she first entered over an hour ago. He took a deep breath, then extended his baton so he landed on her roof with the stealth of a cat. He could faintly hear the sound of some video game being played, but he couldn’t place what one. He hesitantly creep towards her skylight, satisfied to see she was not sleeping in her bed. She must be playing a game. Maybe she’d let him play if things went well.

He gently rapped against the window. The sound of the game didn’t stop.

He rapped again, a little harder. This time he hear something click beneath him, propping up the skylight. But he didn’t see Marinette waiting to greet him under her window, or hear the video game stop.

Whoever unlocked it must have wanted him in, so he pried open the door and peered inside.

He looked around the room, no Marinette insight. Instead what he saw was a small girl, smaller than Puppeteer, dressed in a hamster hoodie, with pink legging and an oversized white shirt. She was currently playing Ultimate Mecha Strike 3, kicking her opponent’s butt by the look of it.

Was Marinette babysitting someone? Or did she have a little sister she never mentioned before?

“Hello,” he called out, sounding more like a question than he meant to. The small girl paused the game and turned to look at him, her dark hair poking out from the hoodie, and her blue eyes wide in… surprise? Fear? Chat couldn’t place a proper word on what the little girl was thinking other than a hero of Paris had just announced himself in Marinette’s room, so some form of shock was probably allowed.

One thing Chat knew for certain after seeing the little girl’s face: Marinette had a little sister.

“Hey,” Chat pulled himself down so he was standing on Marinette’s loft, “I don’t think we’ve met before. I’m Chat Noir.”

The little girl’s eyes went wider, if that was even possible, as she stared at Chat.

“You… you don’t recognize me,” she asked in the cutest voice Chat had heard from a kid.

“If I had to guess, I would say you look like Marinette’s little sister,” responded Chat as he moved down the stairs, “ Speaking of which, is Marinette around? I wanted to talk to her about something.”

The little girl opened her mouth to say something, then immediately shut it before turning back around to continue with her game.

“She’s out.”

“Oh.” Chat nodded, uncertain how to proceed.

“You want to play?”

Chat looked down to the little girl, who had just been declared winner on the screen, holding out another controller to him.

“Sure,” Chat took the controller and sat down next to the small child.

“What’s your name by the way?” Chat selected his character as the smaller girl selected her own, pursing her lips in the tiniest little pout.

“Mari.”

* * *

How did Marinette get into this situation, she did not know. One moment she was happy laying in her hamster hoodie, playing UMS while drinking cola and chips. The next moment she was kicking Chat Noir’s butt in UMS, before fighting with him over the potato chips.

“No Mari, you shouldn’t have potato chips this late,” he insisted as he held up the bag higher than small Marinette could reach.

“But I wannna!” She whined as she pawed at his side, her small hands trying to reach the chips.

“You won’t be able to sleep well if you do.”

“I don’t care!”

Then Marinette remember the cola. She ran away, taking the cola with her as she hid under her desk, using the cat pillow she brought down with her as a protective shield.

“Hahah! I have my cola!” She taunted before taking a giant swig from the beverage.

Chat jumped after her the moment she put the lid back on, Marinette quickly running away and grabbing the potato chips with her free hand.

“Come here,” Chat grumbled as he jumped after her, managing to catch the smaller Marinette.

“Gotcha,” Chat sighed with relief, taking both the cola and chips as he carried small Marinette with one arm. Marinette pouted but said nothing as he set the items on her desk.

“You should probably go to bed now.”

“But I’m not sleepy,” she protested, despite her yawning.

Chat rolled his eyes as he looked around the room.

“Marinette sure is taking awhile,” he wondered aloud.

Right, Chat said he needed to talk to Marinette.

“She’s probably busy,” Marinette yawned. Chat readjusted his holding on her.

“Do you sleep up here or do you have your own room?”

“I can sleep in m-Marinette’s bed.” Marinette almost stumbled saying "my" instead of "Marinette". Hopefully after tonight she wouldn’t have to reference herself in third person anymore than what was necessary as Ladybug.

“Alright.”

Chat took her up the stairs, and set her inside Marinette’s bed.

“Kitty!”  She sat up in realization.

“Yes?”

Marinette frowned before pointing to the ground where her long cat pillow lay.

“Right.” Chat turned around and marched back down the stairs to fetch the cat pillow, Marinette sitting up to watch as he made his way around her room, turning off the games and lights until the light by her beside is the only one that remained on.

“You want kitty behind you or next to you?”

Marinette patted the space behind her, Chat tucking the cat in, while bringing the blanket’s up to Marinette’s neck.

“Goodnight Mari,” Chat wished as he left her room.

Marinette waited, making sure the cat boy was gone. Once she was certain she was in the clear, she could go back to playing video games.

Unfortunately she fell asleep before that.

* * *

Adrien wasn’t sure if one would qualify what he was doing as staring. Sure his gaze was aimed in Marinette’s direction as she talked with Alya across the table from him, but he wasn’t entirely paying much attention.

Marinette had never mentioned a little sister before. He knew Alya had sisters and Nino had a little brother. He knew Marinette was good at babysitting, but Mari looked too much like Marinette to be considered a random child she babysat. Plus the way Mari was able to play UMS last night, using the same moves he had seen Marinette use, made him more certain they were related. Plus their names were similar.

“A-Adrien?”

Adrien was drawn out of his trance by everyone in the group staring at him.

“I’m sorry, what was the question?”

“Um, uh, no question. It’s just, um, you seemed out of it. Is everything alright,” asked Marinette, her glance flittering between him and her lunch.

“Yeah, sorry, just,” Adrien looked around the group, all whom had concerned expressions.

“I saw a little girl, the other day, who looked a lot like you. I was just wondering if maybe you were related?”

That sounded believable right?  Not a direct mention of Mari, but enough where if it was true, she would be able to confirm it.

“What? No… pssh, no relatives here. I mean, I have relative, but not here, in France. They live in China, or elsewhere. Not little sisters, I mean, little cousins, living. Around here,” Marinette stumbled out.

Adrien nodded, looking back at his food he had hardly touched. Guess he would have to try confronting Marinette about it as Chat Noir later then.

He looked up and smiled.

“Shame, she looked exactly like you. Even had cute little pigtails.”

Ok, maybe he overstepped it on the cute, because Marinette began turning bright pink.

“We should investigate, maybe you have an unknown younger twin living in Paris,” exclaimed Alya excitedly.

While Alya went on about twins, her sisters being twins and all, Adrien glanced over to Marinette, who seemed more interested in her lunch than the conversation. Although she wasn’t eating it, instead, mixing around her salad while she frowned, totally in Ladybug thinking mode.

* * *

“Tikki!” Marinette quietly screamed as she entered her room, quickly slamming her trapdoor shut.

“What’s wrong Marinette?”

“Adrien knows!”

“Knows what?”

“He knows about me! Not Ladybug me but degenerate hamster hoodie me,” Marinette groaned as she slunk off to her changing screen.

“But how would he know? You only put on your hoodie when you’re home. Which I still do not approve of.”

“Come on Tikki, its a chance for me to relax.” Marinette tossed her dirty school clothes in her hamper, exchanging it for an oversized t-shirt and leggings. “Plus my school and Ladybug duties haven’t been neglected because of it.”  
“Yet. This could be a bad habit Marinette. You wear the hoodie every night and do this.”

“I’ll be fine Tikki,” Marinette stepped out from behind the changing screen as she snapped on her hamster hoodie, her size shrinking down.

“But if Adrien knows, maybe I should stop.”

She immediately grew back to her normal size.

“But Adrien said I still looked cute.”

She shrunk back down.

“But what if he just means in a little kid sense! I don’t want him to see me as only a kid,” Marinette groaned as she grew back to her proper size, trying to figure out what to do. Chat knew her degenerative side, and apparently so did Adrien, some how. But they both thought she was just Marinette’s little sister.

Marinette was ready to throw off the hamster hoodie and call it a night when she her computer dinged with a notification. She ran over to see a notification that her team was active on a game.

She immediately shrunk back down as she launched the game.

“Duty calls.”

* * *

As soon as dinner was over for the night, Adrien immediately ran towards his room, transformed into Chat Noir before heading out. He ran across the rooftops, hoping Marinette had just finished dinner too so he could still catch her.

He made it to the school in record time, breathing a sigh of relief when he saw Marinette cleaning up the table with her parents, already dressed in home clothes with an oversized t-shirt and leggings. He sat down on the roof to catch his breath as he watched her kiss her parents goodnight, then head up to her room. Tonight he would either tell her he knew about her being Ladybug, or confront her about her “little sister”. Or both. Or would both be too much for one night?

Once he was certain she was up in her room, he launched himself over to her balcony, not waiting to be invited before opening the hatch.

Only to find Mari opening a new bag of potato chips.

“Mari?”

“Chat?”

Chat slid down into Marinette’s room, certain he saw Marinette come upstairs. Did she go back down when he made his way over.

“Is Marinette here?”

“She’s busy. Downstairs. Said she wanted to focus on homework.”

Chat looked over to see Marinette’s school book on the desk.

“Ri-ight. Do you know when she’ll be back?”

Mari shrugged before turning back to the computer screen, starting a new online game.

“Whatcha playing this time?”

“Doki Doki Literature Club.”

Chat nodded, trying to remember why he thought he heard that game before.

“Mind if I play with you?”

“Its a visual novel game.”

“Oh.”

“But you can watch, and maybe help.”

Chat pulled up another desk chair and sat beside Mari as she clicked “New Game”.

* * *

Marinette was frazzled to say the least. Every night for the past week, Chat had come over during her “Hamster Hoodie” time, looking for Marinette, which only ended in them playing games with each other. Which wasn’t that bad. Chat was pretty fun to play video games with.

What was frazzling was how he treated her like a little kid (who could blame him when her size in the hamster hoodie came up to his knee cap). It was endearing, and awkward all at the same time. What if he were to catch her as Marinette in the hoodie? Would he find it as awkward as she did whenever he tucked her in for the night? Or when she would climb him, like a tree, to get back her precious chips and cola?

Marinette had barely been able to do patrol with Chat, quickly dividing the city for them to do it separately, much to Chat’s irritation. She probably should have stayed longer in case he needed to tell Ladybug something too. Or she could have offered to pass along his message to Marinette. As either Ladybug or Mari.

What was Chat’s reason for visiting her anyway? Did he just like her company? Or need help with something? Was he actually crushing on her and kept trying to confess?

Chat was making her frazzled.

Adrien though, after first asking about her supposed “little twin with cute pigtails”, had just been same wonderful Adrien. If anything was different, he seemed to smile her way more often. Even asking of they could hang out sometime. As friends.

Which also left Marinette frazzled as she hid her hamster hoodie, stash of chips and cola before Adrien came over to play games that afternoon.

“Three identities is getting hard to manage Tikki,” groaned Marinette as stuffed it under her cat pillow that was sitting nicely on her bed.

“You wouldn’t have three identities if you gave up the hamster hoodie,” scolded Tikki, still not approving of Marinette’s degenerate ways.

“But it’s so relaxing,” Marinette sighed as she made her way down the stairs. She looked over to her clock to see the time was 15:47. Adrien wasn’t done with fencing until 17:00. Marinette glanced up between her clock and the hoodie.

Maybe she had time for a little game.

* * *

 Adrien checked his phone as he exited the school.

17:14.

He had promised to meet Marinette to hang out after school, maybe finally talk to her about being Chat Noir and telling her he knows she’s Ladybug. But she didn’t know that. She thought they were just going to hang out at her place after school.

Adrien proceeded across the crosswalk and up to Marinette’s apartment.

Before he could even knock on the door, Mrs. Cheng opened it for him.

“Adrien! Marinette told us you were coming over. She should be upstairs,” Mrs. Cheng pulled him inside, handing him a plate of croissants as she guided him to the stairs towards Marinette’s room.

“You two have fun, and let me know if you need anything.”

“Will do ma’am.”

Adrien continued up the stairs, opening the trap door to Marinette’s room.

Only to find Mari at Marinette’s desk, playing some UMS.

“Um, hi?”

Mari paused the game and went wide eyed as she stared at him. She opened and closed her mouth as if to say something, but nothing came out.

“Marinette never mentioned having a little sister before,” he offered.

Mari shut her mouth, looking between him and Marinette’s bed.

“Is Marinette taking a nap?”

Again, Mari said nothing.

“Adrien, is everything alright,” he could hear Mrs. Cheng calling after him. He looked over to Mari only to see she was already next to him, pulling him up into Marinette’s room.

“I’ll go get Marinette.”

Mari zipped down the hatch.

Confused by the situation, Adrien set down the croissants just as his phone rang.

Akuma attack.

Now would be the perfect time to tell Marinette, as they would transform together then go off to save the akuma. But then he got another notification.

The akuma was causing art to disappear at the Louvre.

Identity revealing would have to wait.

* * *

After receiving a question look from her mother, Marinette hid the hamster hoodie between the couch cushions, then zoomed back upstairs.

“Hey Adrien, sorry about that…”

She looked around her room to see Adrien wasn’t there, but her trap door was open.

“Adrien?”

Marinette crawled up to her balcony, Adrien nowhere in sight. She looked over the balcony, satisfied there was no Adrien hanging off the edge.

“Marinette, you have to leave. There’s an akuma at the Louvre,” Tikki flew up next to her cheek.

“But Adrien…”

“Will understand.”

“Right.”

* * *

“Pound it!” Ladybug and Chat Noir fist bumped as Paris returned to normal after defeating the akuma.

Just then, Ladybug’s earrings began to ring.

“Looks like I’m out of time. Bug-out!” Ladybug saluted before launching away, leaving Chat Noir behind.

“Not this time my lady,” Chat murmured under his breath as he waved goodbye to the formerly akumatized person before launching after Ladybug.

Chat made sure to keep his distance as he ran over the roofs of Paris to Marinette’s, jumping directly down into her hatch. Marinette was nowhere in sight.

* * *

Marinette ran up to the bakery, noticing her parents were inside.

“Maman, have you seen Adrien?”

“No dear? Why?”

“Um, well, we decided to go out, when an akuma attacked the Louvre, so we got separated. I was just wondering if he came back here.”

Her parents looked at each other and shook their heads, “No we haven’t seen him.”

“Alright. Thanks.”

Marinette quickly scampered up to the apartment, grabbing her hamster hoodie as she raced to her room.

“Marinette, I’m not sure that’s a good idea, we don’t know if Adrien is still here,” warned Tikki.

“I’ll just say that I’m putting it in the wash for later. If Adrien is up there, he won’t notice the difference.”

Marinette burst open through her trap door, surprised to see Chat Noir lounging on her chaise.

“Glad I finally caught you,” Chat teased as he sat up from his position on her chaise.

Marinette opened and closed her mouth several times. She had prepared for an Adrien scenario, not for a Chat Noir scenario.

Chat patted the space beside him, Marinette wordlessly walking over to sit next to him.

“I keep trying to talk to you, but your sister keeps showing up.”

“Yeah, um, she really likes to play games on my computer.”

“As well as eat potato chips and drink cola at unreasonable hours.”

“Heheheh,” Marinette chuckled, her voice and heart clearly not in it.

* * *

Chat frowned, Marinette was completely stiffened by the situation, not making this reveal thing go any easier.

“Marinette.” Chat stood to face her, just in case she decided to run. Ladybug and Marinette did have a habit of running.

“I know you’re Ladybug.”

Marinette’s eyes went wider, if that was even possible, her mouth dropping open like a gaping fish.

“Wahhh?”

“I’ve actually known for about a week now. I kept trying to talk to you about it, but um, well, you were busy.”

Marinette snapped her mouth shut, her eyes focusing on her lap. Where Chat finally noticed Marinette clutching Mari’s hoodie.

“That’s Mari’s.”

Marinette bit her lip, trying to decide something.

“It’s mine, actually.”

Chat raised an eyebrow as Marinette threw the hoodie around her neck, pulling the hoodie over her head. In a flash, she was Mari, her legs dangling over the side of the chaise.

* * *

Marinette looked up to Chat, his face turning as red as her Ladybug suit.

“I saw this anime called Himouto! Umaru-chan and the girl wears a hamster hoodie when she gets home, and that’s how she relaxes, and well with school, class president, and Ladybug things piling up, it looked like a good idea to, you know, relax,” she explained, Chat’s reddened face not lessening.

“I figured. I’ve seen the show.”

“You have!”

“Gosh, I’m such an idiot,” Chat went pounding his fist against his forehead, Marinette imagining he was thinking about all that occurred between him and “Mari”. Chat flopped over on her chaise so his midsection was next to her, his head and feet dangling of either side of the chaise.

“How could I not put two and two together,” he groaned?

“Well, what did it take for you to figure out I’m Ladybug?”

“Seeing you de-transform in an alleyway.”

Marinette shrugged as she resumed her normal height.

“Same basic principle.”

“So it would probably take me de-transforming for you to believe who I am.”  
“Chat, you don’t have to. I think we shared enough secrets today.”

“That’s not the point Mari. The original point was me coming over, tell you I know you’re Ladybug, then telling you who I am. No anime, no cute classmate turning into a tiny creature of the night.”

“Eep,” Marinette squeaked at the word cute.

* * *

Chat smiled at her squeak as he glanced over at her. He was pleased he could elicit such a response as Chat.

“So please let me show you. Not in a matter of fairness, but for my own sanity. It’s been crazy not telling you this past week.”

Chat rolled over as he sat up a little, watching Marinette’s reaction. Seeing her in the hamster hoodie as her normal self was actually pretty cute.

“Fine, for your sanity,” she relented with a teasing grin, reminding Chat she was also Ladybug. Ladybug, Marinette, and Mari; all rolled into one.

Chat bounced back to his feet, turning to face Marinette.

“Plagg, claws in!”

He felt the wave of magic wash over him, opening his eyes to see Marinette gaping at him again.

“Hey,” he waved awkwardly at her. She quickly shut her mouth as she transformed back into Mari, scrambling past him and onto her bed. Adrien raced up and grabbed her before she could attempt to leapt off her balcony.

“I regret this hamster hoodie,” she groaned as she returned to normal size, Adrien releasing her so they laid side by side on the bed.

“I wouldn’t say that. I got to know you a little better, even though I didn’t know it was you.”

“What about Paris? What if Hawkmoth found out we knew each other’s identities?” Marinette slightly sat up and looked over at Adrien.

Adrien tugged a bit on her hoodie. “I think I found a convenient excuse.”

* * *

Alya and Nino were marching over to the Dupain-Cheng Bakery, both irritated at being stood up by Marinette and Adrien. Sure it was nice for a chance at a one-on-one date time, but the point of this was to get Marinette and Adrien together.

Plus there was the exception of an akuma attack, but that was beside the point.

“Marinette isn’t even picking up her phone,” groaned Alya as she pocketed her device.

“You don’t think they got held up by the akuma do you? They did say they were on their way before the movie started,” argued Nino.

Alya’s eyes lit up in realization.

“What if…”

“What if,” Nino eyed his girlfriend skeptically before she grabbed his hand, pulling him after her.

“Hi Mr. Dupain! Hi Mrs. Cheng,” Alya called out as they passed Marinette’s parents in the bakery.

Alya pulled out a spare key and opened Marinette’s house, pulling Nino up to Marinette’s room.

Instead of hopefully finding Marinette and Adrien making out in Marinette’s room like she hoped, Alya and Nino found two children in hamster hoodies playing video games, eating chips, and drinking cola.

“Was there a child causing akuma we didn’t know about? Or a shrinking one,” asked Nino, looking between the kids. The kids paused the screen, looking back at their visitors, both with wide eyes. One looking suspiciously like Marinette, the other looking suspiciously a lot like Adrien.

**Author's Note:**

> Finally got around to watching Season 2 of Himouto! Umaru-chan. This idea came into my head before when I watched Season 1 because Marinette likes hamsters.  
> Pure fluff and Crack and Oblivious!


End file.
